Powered cartridges and other devices within housings

ABSTRACT

The present invention describes a system and method for supplying electrical power to a device, such as a filter element, located within a housing. In one embodiment, a conductive coil is embedded into the housing base, and a second coil is embedded into the filter element. Current is then passed through the coil in the housing base. Through induction, a current is created in the second coil in the filter element, in much the same way as a transformer functions. This inductive field may interfere with the operation of the various electronic functions, such as communications, sensing or other activities. To overcome this issue, an energy storage component, such as a capacitor, is included in the filter electronics. In this way, the power generated by the inductive field can be stored, and used when the inductive field is no longer present.

BACKGROUND OF THE INVENTION

The use of wireless communication has become prevalent, especially inthe management of assets, particularly those applications associatedwith inventory management. For example, the use of RFID tags permits themonitoring of the production line and the movement of assets orcomponents through the supply chain.

To further illustrate this concept, a manufacturing entity may adhereRFID tags to components as they enter the production facility. Thesecomponents are then inserted into the production flow, formingsub-assemblies in combination with other components, and finallyresulting in a finished product. The use of RFID tags allows thepersonnel within the manufacturing entity to track the movement of thespecific component throughout the manufacturing process. It also allowsthe entity to be able to identify the specific components that compriseany particular assembly or finished product.

In addition, the use of RFID tags has also been advocated within thedrug and pharmaceutical industries. In February 2004, the United StatesFederal and Drug Administration issued a report advocating the use ofRFID tags to label and monitor drugs. This is an attempt to providepedigree and to limit the infiltration of counterfeit prescription drugsinto the market and to consumers.

Since their introduction, RFID tags have been used in many applications,such as to identify and provide information for process control infilter products. U.S. Pat. No. 5,674,381, issued to Den Dekker in 1997,discloses the use of “electronic labels” in conjunction with filteringapparatus and replaceable filter assemblies. Specifically, the patentdiscloses a filter having an electronic label that has a read/writememory and an associated filtering apparatus that has readout meansresponsive to the label. The electronic label is adapted to count andstore the actual operating hours of the replaceable filter. Thefiltering apparatus is adapted to allow use or refusal of the filter,based on this real-time number. The patent also discloses that theelectronic label can be used to store identification information aboutthe replaceable filter.

A patent application by Baker et al, published in 2005 as U.S. PatentApplication Publication No. US2005/0205658, discloses a processequipment tracking system. This system includes the use of RFID tags inconjunction with process equipment. The RFID tag is described as capableof storing “at least one trackable event”. These trackable events areenumerated as cleaning dates, and batch process dates. The publicationalso discloses an RFID reader that is connectable to a PC or aninternet, where a process equipment database exists. This databasecontains multiple trackable events and can supply information useful indetermining “a service life of the process equipment based on theaccumulated data”. The application includes the use of this type ofsystem with a variety of process equipment, such as valves, pumps,filters, and ultraviolet lamps.

Another patent application, filed by Jornitz et al and published in 2004as U.S. Patent Application Publication No. 2004/0256328, discloses adevice and method for monitoring the integrity of filteringinstallations. This publication describes the use of filters containingan onboard memory chip and communications device, in conjunction with afilter housing. The filter housing acts as a monitoring and integritytester. That application also discloses a set of steps to be used toinsure the integrity of the filtering elements used in multi-roundhousings. These steps include querying the memory element to verify thetype of filter that is being used, its limit data, and its productionrelease data. This application also describes an internal transponderfor relaying information to an external monitoring and test unit. Anantenna is arranged adjacent to the transponder on the filter housing.

Many of these applications require that the devices within the housingbe electrically powered. While the use of small batteries may besufficient for some applications, in many applications, and even morepotential future applications, this small amount of power provided bysuch batteries is insufficient to power the electronics within thehousing.

Incorporating a power connector in the filter element to connect to asuitable mating connector in the housing may be problematic. Such asolution requires mating connectors that are capable of toleratingextreme conditions, such as temperature (particularly during molding andsteam cleaning), and fluid flow. Therefore, issues such as the qualityand integrity of the seal between these connectors may be suspect.

Thus, there is a need to reliably provide power to devices, such asfilter elements, enclosed in a housing without sacrificing quality andsafety, and without having to add new materials particularly wherewetted surfaces are involved.

SUMMARY OF THE INVENTION

The shortcomings of the prior art are overcome by the present invention,which describes a system and method for supplying electrical power to adevice, such as a filter element or an electrical component thereon,located within a housing. In some cases, the use of wires inside thehousing may be impractical, due to internal conditions, such as fluidflow, pressure or temperature. This invention requires no physicalconnections between the power source and the one or more enclosedelectronic components, thereby reducing the risk of poor connections,and increasing the useable life of the overall system. In oneembodiment, a housing adapted to receive a filter element in the form ofa filtration cartridge, such as that commercially available fromMillipore Corporation and sold under the name Filter Cartridge HousingSeries 3000, is provided, and a conductive coil is positioned in thehousing base, and a second coil is positioned in the filter element.Current is then passed through the coil in the housing base. Throughinduction, a current is created in the second coil in the filterelement, in much the same way as a transformer functions. This transferfor power requires no physical electrical connection and also places nolimits on the amount of power that can be induced in the filter elementcoil. In a second embodiment, the filter element comprises tangentialflow filtration (TFF) cassettes, and one or more coils are placed withinthe cassettes to achieve the same result. The inductive field mayinterfere with the operation of the various electronic functions, suchas communications, sensing or other activities. To overcome this issue,an energy storage component, such as a capacitor, is included in thefilter electronics. In this way, the power generated by the inductivefield can be stored, and used when the inductive field is no longerpresent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a representative housing base and filter element inaccordance with the present invention;

FIG. 2 illustrates an enlarged view of the housing base and the filterelement in their operative position in accordance with the presentinvention;

FIG. 3 illustrates an alternate embodiment of the present invention;

FIG. 4 illustrates a first embodiment utilizing TFF cassettes;

FIG. 5 illustrates a second embodiment utilizing TFF cassettes; and

FIG. 6 illustrates a graph showing the interaction between the inductivefield and the functioning time.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a representative filter housing base 10 and anassociated filter element 20. In the embodiment shown, the base andfilter element are that of a device Cartridge Filter and Series 3000Housing, commercially available from Millipore Corporation. The filterelement has a membrane, through which materials are passed, and thecorresponding structure or frame necessary to support this membrane.Surrounding this assembly is typically a housing dome, preferablyconstructed of stainless steel or some other non-corrosive material.Also, inlets and outlets are typically present, but have been omittedfrom FIG. 1 for clarity. Housing base 10 typically contains one or morematable portions, such as cavities 30, each adapted to mate with andhold a filter element. These cavities typically have one or more inletand output ports in them, to allow fluid to pass through the filterelement. Into this cavity 30, a filter element 20 is inserted. Thefilter element 20 preferably has a matable portion, such as a smallerend 40, which fits within the corresponding matable portion of thehousing base 10 (e.g., the cavity 30). The matable portion of the filterelement preferably has one or more areas with radially extending membersdefining between them grooves 50. One or more gaskets, or O-rings (notshown), each preferably constructed from rubber or another suitableflexible material, are preferably positioned in the groove createdbetween these ridged areas 50 to effectuate a liquid tight seal betweenthe filter element and the housing base.

In a preferred embodiment, an electrically conductive coil 60 isembedded in the housing base 10, circumscribing the cavity 30. This coilis preferably constructed from electrically conductive material, in theform of a wire and wound to form a coil. In accordance with knownelectromagnetic theory, the greater the number of windings, the greaterthe amount of power that can be transmitted. Preferably the coil isembedded in the housing such that it occupies an area corresponding tothe surface area of the cavity. In other words, the coil extends theentire length of the cavity wall, as shown in FIG. 1. Alternatively, acoil occupying less surface area and extending through only a portion ofthe cylinder is also possible and within the scope of the invention.

A similar coil is also embedded in the filter element. As stated above,in the embodiment shown, the matable portion of the filter has a smallerend that is inserted into the cavity of the housing base. In thepreferred embodiment, an electrical conductive coil is embedded intothis smaller end, preferably extending the entire length of the smallerend, as shown in FIG. 1. However, a smaller coil, which extends only aportion of the length of the smaller end can also be used, and is withinthe scope of the invention.

FIG. 2 shows an enlarged view of the base cavity and filter element.This figure shows the preferred position of the coil in the housingbase, as it extends the entire length of the cavity wall. Similarly, thecoil within the filter element extends the length of the smaller end.When the filter element is properly seated in the cavity, the two coilswill preferably be concentric with one another, thereby preferablydefining two concentric cylinders, thereby maximizing energy transfer.The distance between the coils is important, and therefore it ispreferable to minimize that spacing.

Another embodiment uses methods to extend or otherwise redirect themagnetic field, such as using an iron core. The insertion of magneticmaterial coaxially or magnetic shielding outside the coils allows theembodiment to be optimized for the transfer of power and/or reduction ofinterference with outside electrical components. For example, in oneembodiment, the use of an iron rod within the receiver coil (such as inthe TFF embodiment described below) improves the efficiency of thetransfer of power. In another embodiment, magnetic shielding may be usedto reduce or eliminate electromagnetic interference, or to comply withemission standards, such as those provided by government agencies.

Both coils shown in FIG. 2 are preferably completely encased in plasticso as not to be exposed to the external environment. This improves thereliability of the system and also reduces the potential forcontamination within the filter system.

The number of turns for each coil is an implementation choice. In oneembodiment, these values are chosen so as to create a voltage within thefilter element that can be used directly, without regulation. In anotherembodiment, the number of turns is maximized so as to transmit themaximum amount of energy. The present invention does not require aspecific configuration and therefore, all combinations of turns arewithin the scope of the invention.

A power distribution circuit drives the coil within the housing base,which is also known as the transmission coil. This circuit supplies anAC current or voltage to the transmission coil. Methods of producingsuch a current or voltage and driving a coil are well known to oneskilled in the art and will not be described herein.

The filter element may contain a circuit to regulate the inducedvoltage. As previously stated, a voltage is induced in the coil of thefilter element, which is also known as the receiver coil. The voltage isdependent on the number of turns for both the receiver and transmissioncoils and the voltage across the transmission coil. In one embodiment,these values are selected such that the voltage induced at the receivercoil is directly usable by the circuitry contained in the filterelement. In another embodiment, this voltage is regulated. Voltageregulation is known to those of skill in the art and can be performed avariety of ways. For example, power rectifiers, diodes, capacitors orintegrated circuits can be used to perform this function.

By supplying power to the filter element, a multitude of possibleapplications are possible. For example, devices as simple as LEDs can beutilized. Other powered devices, such as pressure, temperature andconcentration sensors and other sensing devices can likewise be used.More sophisticated components, including network components, such asEthernet, wired LAN or wireless LAN components can also be utilizedwithin a filter element. Incorporating a standard network device withinthe filter would allow it to be connected directly to a network. Infact, the use of such a network component would also provide a uniqueidentification number for each filter element.

In another embodiment, CPU components, preferably hardened components,can be embedded into the filter element. This allows the filter elementto perform onboard calculations and other operations and could, forexample, calculate test specifications based on the housingconfiguration. Other possible devices include wireless LAN devices, suchas BlueTooth® or Wi-Fi® components.

As stated above, in the preferred embodiment, the receiver coil islocated in the smaller open end of the filter element, while theelectronic components are embedded in the closed end of the filterelement. One or more wires, preferably embedded in the plastic casing ofthe filter element, carry the power signals from the coil to theelectronic components.

While the previous embodiment assumes that the housing base is createdwith the coil embedded in it, this is not a requirement of the presentinvention. Retrofitting existing housing bases can be done as well. Inthis embodiment, a small insert, preferably constructed from plastic, isseated within the cavity of the housing base. It is preferably theheight of the cavity and is a hollow cylindrical shape. Within thisinsert is the transmission coil, with one or more wires exiting forconnection to a power source. The insert is placed within the cavity asshown in FIG. 3. In one embodiment, the dimensions of the insert aresufficiently small that the filter element can still be positioned inthe insert. Since the filter element has gaskets or O-rings that areflexible, the slight reduction in cavity diameter does not preclude thefilter element from fitting within the hollow insert. In anotherembodiment, the housing base is modified so as to increase the diameterof the cavity. In this way, the insert occupies the volume thatpreviously was part of the housing base. Preferably, the housing base isalso modified to include a feedthrough so that the wires required by thetransmission coil can pass through the base to an appropriate circuit.

Although described above in reference to cylindrical filters, thepresent invention is equally applicable to other types of filterelements as well.

For example, tangential flow filters (TFF) can also incorporate thepresent invention. As shown in FIG. 4, one or more TFF filters, orcassettes, 100 are typically arranged in parallel, held together with aholder (not shown). This holder typically consists of a plate at eitherend of the TFF configuration, with fastening mechanisms, such as boltsor clamps, passing through the plates and the cassettes, thereby holdingthe entire system together. Preferably, indentations, slots or grooves110 are molded into the TFF cassettes so as to hold them in position.

In one embodiment, the transmission coils are embedded into the endplates that compress and hold the TFF cassettes 100 in place. Thetransmission coils are preferably located in a groove created along theedge of the plate, facing the open side of the cassette 100. This coilis preferably encased in plastic, which is molded into the groove. Theelectrical wires that power the transmission coil can be passed througha hole in the end plate, or attached in some other way.

The receiver coils 120 are placed such that their central axis ispreferably perpendicular to the end plates. The coil 120 is preferablyparallel to the internal membrane and is wound around the outer edge ofthe jacket. Preferably, the receiver coil 120 is placed in closeproximity to the transmission coil so as to affect high powertransmission. FIG. 5 shows one such embodiment, where the receiver coils120 are molded into the outer overmolded jacket 130 in a locationoutside of the typically fluid path. To improve the induction betweencoils, the coils can be designed so as to interlock. In other words, thecoil 120 of one cassette may have a tapered end that extends beyond theend of the cassette. This tapered end then fits in the hole 140 withinthe coil of the adjacent cassette. Alternatively, the coils can bemolded so as not to extend beyond the cassettes for ease of assembly andusage. In another embodiment, a magnetic member such as a rod isinserted through the holes 140 of the various receiver coils to improvethe energy transfer.

In another embodiment, shown in FIG. 6, the receiver coil 120 isembedded in the outer overmolded jacket 130 of the TFF cassette. Thereceiver coil 120 is located in the outer overmolded jacket 130, and isoriented perpendicular to the internal membrane. In other words, itscentral axis is parallel to the internal membrane. As can be seen inFIG. 6, this location is still accessible, even when the TFF system isfully assembled. The transmission coil is then placed in proximity to,or against, this outer jacket 130 to induce power in the TFF.Preferably, this transmission coil is embedded into a fixture that isthen placed in proximity to, or against, the outer jacket. In the casewhere multiple TFF cassettes 100 are stacked together, multipletransmission coils can be utilized. Alternatively, multiple coils can beplaced within a single fixture. Finally, multiple fixtures, eachcontaining a single coil, can be used to supply power to each of thecassettes.

While this application describes cylindrical and TFF filter elements,the invention is not so limited. Any filter element, regardless ofshape, can be self powered by placing a powered transmission coil inrelatively close proximity to a receiver coil contained within thefilter element, such that induction occurs. The above two filter typesare simply illustrative of the scope of the invention, and are not meantto limit it to only these embodiments.

In another embodiment, coils are inserted within connectors used tointerconnect completely disposable filter housings to the supply tubesor other components. The transmission coil is preferably formed into theouter connector, while the receiver coil is formed in the disposablefilter housing. These connections simplify the wiring scheme fortransmitting power to a filter, since fluid and electrical interconnectscan be made jointly. In addition, since the electrical connection ismade without the use of wires, this method reduces the risk ofunsanitary contamination by retaining the electrical components within acleanable and/or drainable conduit.

The inductive coupling allows the generation of power within the filterelement or cartridge. However, it may be possible that the inductivefield required to generate power makes other functions, such as wirelesscommunication difficult, if not impossible. Thus, in some applications,it may be necessary to disable the inductive field before performingother functions.

In one embodiment, the filter element comprises an energy storagecomponent, such as a capacitor. In the preferred embodiment, thiscapacitor, along with the other electronic components are encapsulatedin the filter element, so as not to be exposed to the conditions withinthe housing. For example, this capacitor may be located in the end cap,or the end of the filter furthest from the matable portion. When theinductive field is active, energy that is not immediately used is storedby the storage element, available for later use. The size of the energystorage component is dependent on several factors, such as the powerconsumption of the filter element's electronics and the amount of timethat the electronics are required to operate on a single charge. Thefactors used to determine of the size of the energy storage componentare well known to one skilled in the art.

Thus, based on the size of the storage component and the total powerconsumption of the electronics, the autonomous running time (A) can bedetermined. This time is the maximum amount of time that the electronicswithin the filter can operate before another induction cycle is requiredto recharge the capacitor, or other energy storage component.

To operate the filter element, the inductive field is enabled, therebyallowing the energy storage component to charge. The inductive field isthen disabled, and other functions, such as sensing or wirelesscommunications can take place. These activities can persist for a timeless than A (the autonomous running time). The time that activity takesplace is called the functional time (F). Thus, F must be less than A forproper operation. Some margin should also be incorporated whencalculating F, such that the filtering system has time to switch offcorrectly, before entering recharge mode. This time is referred to asthe safety/switching time (S).

To transmit long streams of information, or perform lengthy functions,it may be necessary to charge the energy storage component multipletimes. For example, the energy storage component could be charged andthen the filter element may perform the first part of a wirelesstransaction. After time F, the wireless communication is suspended, andthe storage component is recharged by enabling the inductive field.After a recharge period (R), the inductive field can be disabled and thefilter element is then able to resume the wireless transaction. Ifnecessary, the wireless transaction can be suspended multiple times toallow the storage component to be recharged.

Because the filter element electronics are independently powered, it ispossible to utilize protocols other than traditional RFID protocols,thereby potentially allowing faster transfer rates. Other known wirelessprotocols such as IEEE 802.11a, 802.11b, 802.11g, Bluetooth®, orproprietary protocols utilizing amplitude or frequency modulation can beused.

In one embodiment of the present invention, separate means is used tocontrol and coordinate the various activities. For example, this meanscan be used to assert a first signal when the inductive field is to beenabled. A second signal (or alternatively, the deassertion of the firstsignal) signifies that the inductive field is to be disabled. A thirdsignal then notifies the electronics that it is safe to operate orcommunicate. A fourth signal (or alternatively, the deassertion of thethird signal) then notifies the electronics to suspend activity becausethe inductive field will be enabled shortly.

Thus, the time from the assertion of the first signal to the secondsignal (or the deassertion of the first) must be greater than, or equalto R, defined above as the required recharge time. The time between thesecond signal (or the deassertion of the first) and the third signal isthe safety/switching time, S. The time between the assertion of thethird signal to the fourth signal (or deassertion of the third) isdefined as F, the functional time. Finally, the time between the fourthsignal (or deassertion of the third) and the next assertion of the firstsignal is also the safety/switching time, S. Thus, a complete sequenceincludes a recharge period, two safety/switching periods, and afunctional period. As stated above, this sequence can be repeatedmultiple times, as required.

Furthermore, although the above embodiment assumes a repeatablesequence, this is not required by the present invention. As long as theenergy storage component is adequately charged, the inductive field canbe disabled, allowing the electronics to operate for an autonomousperiod of time. Additionally, once the energy storage component ischarged, there is no requirement that the functional period beginimmediately thereafter. The component is preferably able to store theenergy for extended periods of time.

1. A filtering system, comprising a filtering element comprising anembedded electrical conductive coil.
 2. The filtering system of claim 1,further comprising a housing having a first matable portion forreceiving said filtering element, and wherein said filtering elementcomprises a second matable portion for insertion into said first matableportion in sealing relationship.
 3. The filtering system of claim 2,wherein said coil is embedded in said second matable portion.
 4. Thefiltering system of claim 2, wherein a second electrical conductive coilis embedded in said filter housing.
 5. The filtering system of claim 4,wherein said second coil is energized by an associated circuit.
 6. Thefiltering system of claim 4 wherein said second coil and said embeddedcoil define concentric cylinders.
 7. The filtering system of claim 1,wherein said filtering element comprises a TFF filter, having aninternal membrane.
 8. The filtering system of claim 7, wherein said coilhas a central axis and said axis is parallel to said membrane.
 9. Thefiltering system of claim 7, wherein said coil has a central axis andsaid axis is perpendicular to said membrane.
 10. The filtering system ofclaim 7, wherein said TFF filter further comprises a magnetic memberpositioned within said coil.
 11. The filtering system of claim 10,wherein said member comprises an iron rod.
 12. The filtering system ofclaim 1, wherein said filtering element comprises electronic components.13. The filtering system of claim 12, wherein said filtering elementfurther comprising an energy storage component adapted to store energyreceived by said coil.
 14. The filtering system of claim 13, whereinsaid energy storage component comprises a capacitor.
 15. A method ofwirelessly supplying power to a filtering element comprising: a.Providing a first electrical conductive coil in said filtering element;b. Providing a second conductive coil in proximity to said first coil;and c. Energizing said second coil with an alternating energy source.16. The method of claim 15, wherein said energizing step is performedcontinuously.
 17. The method of claim 15, wherein said filtering elementcomprises an energy storage element and said energizing step isperformed intermittently.
 18. The method of claim 15, wherein saidfiltering element comprises an energy storage element and saidenergizing step is performed at regular intervals.
 19. The method ofclaim 15, wherein said second coil is embedded in a housing containingsaid filtering element.